Hyper-V: when creating an external switch, the host loses the Internet in the BROWSER, but there is access to it via RDP, why?

Question

Computer networks

Windows 10 Pro in the data center. Installed Hyper-V to run virtual machines.
I should have VMs with white IPs, for this I create an external switch.
As soon as the switch is created, the host loses the Internet (I can’t open any site in the browser, I can’t ping anywhere). Moreover, it is available via RDP, I can also ping it.
Only I delete external switch - everything works. Virtual machines connected to this external swtich see the Internet and work.
What could be the problem? Recently I set up the same on the hetzner - everything is like clockwork, the Internet did not disappear.
There is some mystic here.

Answer 1

It turns out that Hyper-V erased DNS server records when creating an external switch. At removal - returned. Registered on the main connection again - everything worked correctly.